Water-resistant carboxylic acid-polyhydric alcohol resins



Patent ed Apr. 24, 1928.

UNITED STATES PATENT' OFFICE.

CHARLES R. DOWNS, OF CLIFFSIDE, AND LOUIS WEISBERG, OF GBAIdC LWOOD, NEW

sirablc products which are then among the, 'very best -1nsulat1ng materlals available to' JERSEY, ASSIGNORS SEY.

To THE. BARRETT COMPANY, 11 CORPORATION or NEW J1m- .WATER-BESISTANT CARBOXYLIC ACID-POLYH YDRIC ALCOHOL BEQINS.

No Drawing. Original application filed December 22, 1920, Serial No. 432,408. Divided and this application filed September 7, 1921. Serial No. 498,895.

'This application is a division of our application, Serial No. 432,408, filed December 22, 1920 and is directed to the matter defined by the. claims appended hereto and forming a part hereof.

' ,Resinous materials of widely different properties have heretofore been made. from glycerol by suitable combination thereof with a dibasic aromatic acid alone, a dibasic aliphatic acid alone and also with a mixture of varying proportions of-both an aromatic dibasic and an aliphatic dibasic' acid. See

1,0'91,627,'Mar. 31, 1914; 1,091,628, Mar. 31, 1914; 1,091,732, Mar. 31, 1914; 1,098,728, June 2, 1914; 1,098,776, June 2, 1914; 1,098,777,

June 2. 1914; 1,108,329, Aug 25, 1914;.

1108,3330, Aug. 25, 1914; 1,108,331., Aug. 25, 1911; 1,108,332, Aug. 25, 1914;v 1,119,592, Dec. 1,1914.y W

In the case of those materials from glyceroland phthalic acid (an anhydride-fornfing aromatic dibasic acid) alone this combinationhas been observed to pass through three stages, a first solid stage (the A-stage),

a second solid stage (the B-stage) and a'third solid stage (the C-stage).' The ultimate industrial utility of these resinous produzts lies in their use in molding-and like compositions. For this the above-describedC- stage product is very superior to the corresponding B-stage product and can be used successfully in a large number of cases where the- B-stage' product is useless.

In the case. of those materials from glycerol and a illllttSlOtLllPlltltlC ac d or a mixture of dlbasic aliphatic acid and an anhydride-forming dibasic aromatic acid, a solid product other than that corresponding to the B stage product of theglycerol-aromatic dibasic acid grouphas-ncver been described or indicated, although such B-stage products have themselves been known for many years.

N ow, remained -for us to discover that these relatively useless B-stage products can be converted into very use'fuland highly-- dcthe industries.

substantial manner;

useful C-stagc products can beniade from the less useful B-stage products resulting and an aliphatic dibasic acid. Furthermore, we have also discovered that a 't-ribasic aliphatic acid, such as citric acid andmalo malic acid, can be eniployed in place of di--' basic aliphatic acids in producing useful C- stage products either alone or in-mixture U. S. Patents: 1,082,106, Dec. 23, 1913;

with the above-named aromatic acids.

In converting these relatively useless 13-. stage products into our new products, we have thereby caused the: latter. to retain substantially allof the elasticity and flexibility of the B-stage products from which they are respectively made, while we have at the same time increased the electrical insulating properties of our new products beyond that of the corresponding B-stage products. These 'benzoic acid and chlor-benzoyl-benzoic acid,

changes, alone or together, would not add; to the utility of the B-stage products in any 9 However, our new products do differ from the B-stage products fror'n which they are respectively derived in-one most essential particular and the one which enables our new products to be used under'circumstances where the corresponding B-stage products cannot be employed atall. These B-stage products are all decomposed or so altered by water that they cannot be employed in places where water contact is unavoidable such as in submarine cables or in exterior and openly exposed-positions where they are subject to action of dew, rain, shower frost.v The '1- stage products under. these conditions become soft or spongy or'porous, lose in elasticity and flexibillty and also lose in co? hesiveness, resistance to shock, friction and to the passage of electric current, while our new products suffer no material changein any or all of these respects through such.

water contact, while at the same time they can equally well be employed in any and all other uses to which these B-stage'products I have been successfully put. In addition We have also discovered that d To effect this change of the old B St-age products above referred to into our new products, we apply prolonged and high heating to these B-stage products until the change to our new products has been satisfactorily effected. -In general, this is the same means employed to convert the B- .stage products of the glycerol-phthalic acid resin into the corresponding C-stage product. (See U. S. Patent 1,108,330, August 25, 1914. V

In general, these A-stage products we operate with are hard withoutbeing sticky and are fusible; upon proper heating these A-stage products all become infusible and,

reach the B-stage which B-stage products,-

. when submerged in boiling distilled water,

becomes coated with a bloom, always in less than two' minutes; these B-stage products, when further properly heated,- remain infusible but lose the above described sensitiveness to water when the C-stage has been reached. These properties are so sharp and.

so characteristic that an operator can, with certainty, determine when he hasarrived. at each of these three stages, when making these materials in bulk.

We have employed the following olybasic aliphatic acids; among the di aslc acids we have employed and found useful are the following: fumaric acid; maleic acid; .malic acid; succinic acid" and tartaric acid; among the tribasic acids we have em ployed and found useful are citric acid and malo ,malic acid.

Malo malic' acid is represented by the following formula, ,to wit,

HOOC-Ofla-CIL-COOH dcH,-cH oH -coon We'have employed the following mixtures of the foregoing as well as others 'notmentioned below. The figures in the table represent the molecular:proportions of each to designate both the acid as such equivalent anhydride.

Accordingly, the expression phthalic acid as used above and hereinafter, when not otherwise specified or indicated, is intended or its We have emplo ed-phthalic acid, -an aro-' ma tic dibasic aci both 'as such and as its anhydride, in. mixture with the foregoing dlbasic aliphatic acids, as shown, for example, in the following table:

No Phtl allc Fumaric Maleic Mal'c succinic Tartar-1c acid acid j acid aci acid acid 1. 1.0 1-0 2. 1.5 0.'& 3- 0.5 1.5 4 1.0 1.0

i ii 10 1.0 1.0 1.0 Q 1.0

\Ve have employed glycerol, glycol, diglycei'ol and triglycerol, all- 0f which are polyhydric' alcohols or polyhydric alcoholic bodies. \Ve make no claim to a resin made fron'i phthalic anhydride alone because this is the-subject of U. S. Patent 1,108,330 of August 25, 1914. We have discovered, however, that diphenic'acid, LS-naphthalic acid and the benzoyl-benzoic acids form with the above mentioned alcohols resins which are unaffectedby water and we herein claim these resms as part 'ofour .inventlon. Of

the various benzoyl-benzoic acids we have used benzoyl-benzoic acid, methyl-benzoylbenzoic acid and chlor benzoyl-benzoic acid, which we made by condensation of phthalic anhydride with benzol, toluol and. chlorbenzol respectively in the presence of aluminum chloride," in the manner well known to chemists, and have obtained satisfactory resins. 5

We have also maderesins with each of these aromatic acids mixed with one or more of the previously mentioned vpolybasic aliphatic acids and have obtained satisfactory and useful results.

PRODUCING Tnnsn Pnontrors IN BULK.

. Ewamp le I'-Pmt A.

A-stage res-in from glycerol and m'alezc twirl.-Heat together quantities of glycerol andmale'ic acid in the proportion ,of one molecular weight of glycerol to one, molecular weight of acid. The acid dissolves.

forming a homogeneous-mass. As the heating is continued, the melting point gradually rises, andthe material, which at first is -quite sticky and viscous, eventually loses its stick ness and becomes mo-resohd when cold. The completion of the first reaction can be'aScertained byv taking out a small sample, andallowing it to cool. If the cooledv product is viscous or tenacious but I not sticky, the reaction has gone far enough.

At this stage the product is soluble in acetone, making a clear solution useful as a varnish. By this time the melting point is usually over C. and may be as high as 120 (3) (melting points taken by the method described on page 821, Vol.10, journal of Industrial and Engineering Chemistry). The time required to reach this point" free product maybe obtained directly, howmay vary according to the temperature at which the heating is conducted, the bulk of the material employed, and the rate=of stirring. It is seldom advantageous to let this temperature exceed 200 C., as it is then difficult to control the next step in the reaction. On'the other hand, it is desirable to keep the temperature as high as po-ss'ble (i. e. as near 200 C. as possible) because the reaction otherwise proceeds slowly. For example, a batch of two pounds may be converted at170 C. in approximately 20 hours.- Ifthe material is cooled before the next stage of the reaction sets. in. the product ob tained is fusible and soluble in cold ace tone. This resin is also soluble at room temperature in ethyl alcohol and ethyl acetate although not so much as in acetone. It dissolves slightly in benzene. Cold water acts on it rapidly, causing it to become discolored and soft.

Example PP/iii B.

geneous by comminuting it and then molding it under heat and pressure. A bubble ever, by heating ata temperature properly at or near the melting point of th k-stage resin; the maximum temperature should not be above about 135 C. and the temperature me be as lowas- 0.01 lower. By whichever method it is obtained, the resin isinfusible and has'no true melting point,

. althoughit softens sufliciently to be molded under heat and pressure. It is insoluble in acetone, ethyl alcohol, and ethyl acetate, but on standing in contact with any of these inaterials for a considerable time,- the finely powdered resin swells and forms a sort .of jelly-like mass. For example, a batch oftwo pounds may be converted at 135 -C. in

aboutten hours from the A-stage resin to the B-stage resin.

I Example I-Part U.

O-stage resi/n. from glycerol aind malez'c ncirL-J-Ieat the product from Example I-- Part B to a temperature" of 170'200 C. until a test specimen when submerged for two minutes in boiling d stilled water does;

' not show a bloom on its-surface. The time re-.

quired to accomplish this change depends on the temperature used and on the bulk of time is requiredto equalize the temperature.

The final temperature may be as high as 250 C. when time is important. For example, a batch of two pounds may be converted at 110 C. in approximately 30. hours. i In place of maleic acid otExai'nple I, we have used the followingmalic acid; fumaric acid; succinic acid, and malo malic acid, and with satisfactory results. Moreover, we have used various mixtures of these acids as well as mixtures containing one or more of these'acids together with pht-halic acid.

These 'final C-stage products are insoluble at room temperature in the following s01- vents: acetone, ethyl alcohol, benzene, ethyl acetate, chloroform, turpentine, ether, linthan that of the respective B-stage resins,

from which they are derived. -The new products, moreover, are resistant to cold and to boiling water. Prolonged contact with cold water does not diminish the lustreprpolish of the surface, and the water remains neutral to litmus. They are substantially un'alttacked at room temperature by 20% solutions of sulphuric, hydrochloric, nitric,

or acetic acid, but they will not withstand concentrated sulphuric acid or hot concentrated nitric acid. They are not materially attacked within one hour by a 20% solution 'of caustic soda at the ordinary room temperature. However, on boiling in contact with this solution, the resins are decomposed, forming alcohols and sodium salts correspending or related to the alcoholsand acids used in their manufacture.

While these new G-resins can be used as such for certain purposes, the best. most convenient and practical method of manufacture is to apply the final heat treatment at the place or in the form of their ultimate use.

.' This is particularly the case when fillers are to be incorporated with the resin, as it is often more convenient to compound the resin and fillers before the final heat treatment is applied.

Forexample, the finished C-resin may be ,finely, ground, mixed with a suitable filler if desired, and molded by the application of heat and pressure in the way usual in such pulp and the like, which have some mechanical strength of their own, but also the cheaper non-fibrous fillers, such as talc, rotten stone, wood flour, ground asbestos and other like inert powdery materials having no spe- 1o cial mechanicalistrength of their own.

Ewample H. ProddoimQ a molded article containing U- resin from the B-re8in.-The B-resin and the 1 filler, or fillers, are ground separately and then thoroughly mixed in the way usual in such operations. All the materials must be finely oundto produce an even mixture. The rel tive proportions of resin and filler will naturally var according to the particu lar purpose for w iich the molding com cs1- tion is intended. The mixture thus pro uced may be moldedunder heat and ressure, and the final heat treatment, as in -xample I' Part C, then applied with the molded object still in the mold, or the heat treatment may be applied first and the composition then molded. It is not always necessary to carry out the entire heat treatment in-the mold, and the molded objectmay be removed as soon as'it has attained suflicient rigidity to maintain its proper form, under further heating, thus releasing the mold for further use and consequently eheapening the process.

Example Ill.

Producing a molded article containing 6'- resin from the B-resin.The B-resin is finely ground and allowedlto stand in contact wit acetone for a considerable time. dered resin swells and forms a jelly-like mass, which is also a suitable form for compounding with a large proportion of filler by kneading or passing between rolls in the usual way in such operations. The composition thus produced is heated to drive off any excess of solvent and may then be handled as in the preceding example. 'Alternatively, the composition may be molded before driving oif thesolvent, and the solvent may then be driven off while the object is f Example V. I Prodnlcing a molded article containing 0- resin from the A-resin-The -A -r esin is melted and the finely ground filler added thereto. The mixture is thoroughly stirred heated until it becomes infusible and has thus reached the, B-stage. Heating" is continued beyond this point as in Example I, to the C-stage; the composition is then ground and molded under heat and pressure -mthe usual way. Alternatively, the com- The pow-' position is heated only to the B-stage and is then molded and treated as under Example II.

In makinga C-stage resin which is to subsequent molding operation suflices to produce a finished C-stage product.

. Our new products can be distinguished with certain from all other heretofore known products by making the following. two tests: v

I. Place a specimen thereof in boiling distilled water; if its surface remains bright and does not become dull in two minutes, it is water-resistant in the sense we have herein used and will hereafter use that expression.

II. Boil a specimen, say 1 gram, with ten timesits bulk of a 20% solution of caustic soda in water until all or nearly all has gone into solution; filter; cool; acidify with hydrochloric acid. From the product of these' operations'tartaric acid, fumaric acid or succinic acid can all be recovered as such by means usual with chemists for such purposes, from such resins in whose production they have been employed. -Maleic acid and malic acid may be recovered partly as such, but these acids, when used for-making our new product, may also be recovered entirely or in part only as fumaric acid, which is a wgell known transformation product of each of those tWoacids. 1

We have described; generally a continuous and continuing procedure from a. mixture of glycerol and an acid or acids to the final water-resistant C-stage resin, but we wish it to be understood that either such a continuous or such discontinuous process can be used with equal satisfaction. That is, we may proceed from the glycerol and acids to either the A-stage or the B-stage and subsequently to the C-stage, or we maybegin with an A-stage or B-s'tage resin and proceed to U-stage resin therefrom.

These resins all belong to the general class of plastics, and while we have specifically mentioned that they can be used to produce a molded article. it must be obvious to all that they are by no means restricted to such enumerated uses but can be used in many other places and in many other operations and for many other purposes where plastic materials can be used. It'is also obvious that our invention includes these resins whether produced and used as such or whether produced in admixture or association with other ingredients, or used in admixture or association with other ingredi- =ing the association or admixture i f mprises heating a-tribas1c aliphatic car"- ents, and that theterm .resinas used in...-

the claims is notto be construed as excludof other ingredients with said resins.

We claim:

1.' The process of making' airesin' which tween approximtely 170 1 and 200 C; for about 20hours, then below 135 C. for about 10 hours and finally at a higher temperaturift, until a water-resistant resin results. T 2. The process ofmaking aresin, whicliboxylic acid and glycerol between ap roxi mately 170 and 2009 C. for about'20 cuts,

4 finally at a higher tem rat'ure water-resistant resin 'resuts.

' dibasic carb dibasic carboxylic acid --and' -apolyhydric polyhydric Y alcohol until a. water-resistant erol until a water-resistant resin results.

then below 135. Cafor about 110 hours and until I a 3. The process of making a resin, which comprises heating a tribasic aliphatic carboxylic acid,- an anhydride formingaromatic ylic acid and glycerol .until a water-resistant resin results; 4. The-processof n "a resin, which comprises heating a tribaslc aliphatic ca'r--' boxylic acid, an anhydride forming aromatic alcohol until a Water-resistant resin results. 5. The process of making a.resin,which comprises heating malo-malicv acid andra resin results.'

6. The rocess ofmaking-aresin, which] comprises eating malo-mahc acid and glyc I 7. The process of making-a resin, -whi ch comprises heating -'1nalo-malic acid, an an- I hydride forming aromatic dibasic carboxylic 1 acid and glycerol until, a. water-resistant, resinresults.'

8. The process'of making a resin,- which comprises heating malo-malic acid, anjanhydride formin .aromatic-dibasic'carboxylic acid and apol'y ydric alcohol a' water-.

. resistant resin results.

,becbtained from an anhydride of a dibasic 9. A water-resistant tribasic aliPl iatic-car water-resistant resin such as can .be

'19. The com rises eating malo-malic-acid phthalic resistant resin results; SAUL-The of makin cbtainedhem phthalic acid and glycerol.

natures.

carboxylic'aromatic acidz, a tribasic aliphatic carboxylic acid and a polyhydiic alcohol.

.12. A water-resistant "resin-such as can be Qobtainedj-from ananhydride of a dibasic I 'ca'rbox'ylie aromatic acid, a tribasic aliphatic carbox liclacit'l and glycerol.

- comprises heating a tribasic aliphatic 'car---' X boxylic acid and a polyhydric' alcohol be- 13. water resistant, resinsuch as can be obtainedirom malo-malic acid and a. polyobtained'from "an anhydride of a dibasic carboxylic aromatic acid, malo-malic acid and a o'lyhydric alcohol.

16.. water.- i tant resin such as can be obtained froml=-an anhydride of a dibasic 17 A f liter-resistant resin suchas can be obtained from phatic carbo alcohol.

piht-halic acid, a tribasic aliy c acid and a polyhydric phaticcarboxyhc acid and glycerol.

.a resin, which 70 .carboxylic aromatic acid, malo-ma-lic acid *andglycexol. J

water resistant IQSlIl'SllCll as can be 1 obtained from phthalic acid, a tribasic' aliaci and apolyhydric alcoholun't a water'- a resin, which fgbln "ating malo-mahc acid, phthalic ,;ac" glycerol a water-resistant 21;,The 'r s of making a resin, which comprises eating a tribasic aliphatic careatinga trihasicaliphatic car.-

'- boxyli'c acid, phthalic acid and glycerol until a water-resistant results.

23. A water-resistantresin such as' can be obtained from acid, and a pol ydric alcoh v 24. A water resistanturesinsuch as can be acid, malo malic fihtha'lic. acid malo-malic 'j testlmonywhereof we allix our sig- CHARLES a nowns, LOUIS WEISBERG. 

